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Biomedical subjects

G Benker

Publications and source records attributed to G Benker.

At least 127 records · Page 7Linked to original sources
PubMed1979

Gel filtration studies of serum growth hormone in acromegaly following bromocriptine administration.

Sera of 7 patients with active acromegaly were fractionated by Sephadex G-100 chromatography and the effects of bromocriptine on the concentrations of total growth hormone (hGH) and its different molecular forms studied. Three immunoreactive peaks were observed, corresponding to molecular weights of about 20,000 ('little hGH'), 40,000 ('big hGH'), and more than 100,000 ('big big hGH') Following bromocriptine administration, there was significantly more reduction of 'little hGH' than of 'big big hGH'. Careful interpretation of these changes is required in view of the possible influences of sample storage and handling on hGH heterogeneity. We suggest that either bromocriptine acts differentially on the release of 'little' and 'big big hGH', or that these components differ in their metabolic half-life. However, even the suppression of 'little hGH' is insufficient to explain the clinical response of the disease to bromocriptine.

Acromegaly↗
PubMed1979

Fast imaging in flow: a means of combining flow-cytometry and image analysis.

The morphological identification of cells by flow cytometry is difficult. Usually cell sorting and microscopical analysis have to be used in addition. Morphological analysis is simplified by taking cell pictures from a range of particular interest immediately during flow cytometric analysis. Instruments using the video scanning technique for fluorescence imaging are slow and expensive (8, 10). Morphological information can also be obtained by transmission imaging of cells in flow, which requires shorter exposure times. Therefore a cell volume activated flow imaging device has been developed which operates at flow speeds up to 5 m/sec and which depicts transmission images of selected cells on a 16-mm film by a nsec flashlamp illumination. An electronic unit detects the particles in the optically accessible orifice, performs the pulse height analysis, triggers the flashlamp if particles are in the preselcted range of interest and feeds the film. The instrument is capable of delivering up to 150 pictures per second and works either as a flow microscope in which the cells in the preselected volume range are directly observed, or as a picture system in which the cell pictures are stored on the 16-mm film for documentation or for image analysis.

Cell Count↗
PubMed1979

Large-scale preparation of highly purified pyrogen-free human growth hormone for clinical use.

A method is described for the large-scale isolation of highly purified human growth hormone for therapeutic use. The hormone was extracted from frozen pituitary glands under mildly alkaline conditions. Purification was effected by gel filtration and ion-exchange chromatography. The final product was pyrogen-free and had a potency of 2.5 i.u./mg measured by bioassay against the current international standard. The yield of growth hormone/gland was approximately 5 mg.

Chromatography, Gel↗
PubMed1979

[Effect of 17-alpha-hydroxyprogesteronecapronate on sodium excretion and the renin-angiotensin-aldosterone-system in humans].

In seven healthy male subjects, a natriuretic effect of 17 alpha-hydroxyprogesterone caproate (17 alpha-OHPC) was demonstrated. Three of these subjects were kept on an uncontrolled diet and were examined over a period of 12 days. To the remaining four subjects, a single dose of 250 mg 17 alpha-OHPC was given intramuscularly after four days of intake of a chemically defined diet (Vivasorb). In this second test procedure, blood samples were taken in the recumbent position every two hours throughout a period of 12 h after the injection. For two more days and during the days before the administration of 17 alpha-OHPC, blood was taken at 8 a.m. before getting up from bed in same intervals, urine was collected for analysis of sodium and potassium excretion. During the first 12 h after the injection of 17 alpha-OHPC, the urinary sodium/potassium ratio significantly increased in all subjects. Plasma renin activity showed no characteristic changes at this time, whereas the plasma concentrations of aldosterone and cortisol decreased. The decrease of cortisol concentration started immediately after the injection and was more pronounced than that of plasma aldosterone. During the following 36 h, renin activity as well as aldosterone and cortisol concentrations in plasma showed an increase; in contrast, the sodium/potassium ratio decreased. On the basis of these results, the following effects of 17 alpha-OHPC are discussed: (1) an acute natriuresis which may be due to a competitive inhibition of aldosterone at the renal tubules, and (2) an inhibition of pituitary ACTH secretion or of adrenal steroid biosynthesis.

Adult↗
PubMed1977

[Combined doxorubicin and bleomycin treatment of metastasising thyroid carcinoma: results in 21 patients (author's transl)].

The effectiveness of combined cytostatic treatment with doxorubicin and bleomycin was analysed in 21 patients with metastasising thyroid carcinoma which had progressed despite both surgical and radiotherapy. Tumour histology (anaplastic carcinoma in 50%), age and general condition of all patients pointed to a poor prognosis. Significant success (full or partial remission) occurred in eight patients. It is possible that these results can be improved if chemotherapy is started earlier and other cytostatic drugs are used in case of failure of treatment.

Adult↗
PubMed1977

Treatment of isolated gonadotropin deficiency in men with synthetic LR-RH and a more potent analogue of LH-RH.

Six patients with idiopathic isolated gonadotropin deficiency (IGD) were treated with 100 microgram LH-RH s.c. 3 times daily, leading to subnormal increases of serum gonadotropin (Gn) and testosterone (T) levels, and promoting puberty from stage I to stage II-III of TANNER. S.c. administration of 100 microgram of the more potent and longer-lasting analogue 6-D-Leu-10-Des-Gly-ethylamide-LH-RH induced LH and FSH rises after the very first application in these patients for more than 12 h. However, long-term therapy with the analogue (100 microgram s.c./day) did not improve hypogonadism. Paradoxically, on daily treatment (8 patients) with 6-D-Leu-10-Des-Gly-ethylamide-LH-RH the FSH serum levels fell after 1 week and the LH levels after 8 weeks of treatment.

Adolescent↗
PubMed1976

Long-term treatment of acromegaly with bromocryptine: postprandial HGH levels and response to TRH and glucose administration.

Fourteen patients with acromegaly were treated with bromocryptine (CB 154, Sandoz), 4 X 2.5 mg, for periods of up to eleven months. One patient did not tolerate the drug, ten of the remaining thirteen experienced considerable clinical improvement. There was a dose-dependent suppression of plasma growth hormone levels, but growth hormone response to TRH injection and to glucose administration was still present during therapy although reduced. TSH response to TRH was not significantly altered. The suppressive power of bromocryptine on growth hormone appears to be related to the mechanism by which TRH stimulates growth hormone secretion in acromegaly, but long-term administration of this drug may be successful in spite of an absent response to TRH in some cases. Bromocryptine appears to be a safe and effective drug for the treatment of acromegaly.

Acromegaly↗
PubMed1976

Effects of growth hormone release-inhibiting hormone and bromocryptine (CB 154) in states of abnormal pituitary-adrenal function.

Growth hormone release-inhibiting hormone (GHR-IH) was administered to five patients with abnormal pituitary-adrenal function. There was immediate suppression by about 50% of ACTH levels in two patients who had undergone bilateral adrenalectomy because of Cushing's disease; one of them had Nelson's syndrome. Bromocryptine (2-5 mg) suppressed ACTH levels by 62-67% for more than 6 h in these patients. GHR-IH did not significantly influence cortisol secretion by an adrenal carcinoma and only slight changes were seen in two patients with Addison's disease. The possible therapeutic implications are discussed.

Adrenal Gland Diseases↗
PubMed1975

Bromocriptine treatment of acromegaly.

The effects of oral bromocriptine in acromegaly have been studied. A dose of 5 mg six-hourly suppressed circulating growth hormone (GH) levels in nine out of 11 patients treated for seven to 11 weeks. This was associated with considerable clinical improvement in all patients, with abolition of excessive sweating, reduction in soft-tissue thichening, loosening of rings, decrease in shoe size, improvement in facial features, and loosening of dentures. Metabolic changes included improvement in glucose tolerance and reduction in hydroxyproline excretion. Unlike the actions of growth hormone release inhibiting hormone the suppression of GH was not accompanied by a reduction in insulin or glucagon secretion, though prolactin levels were suppressed. Side effects other than mild constipation were not seen when the full dose regimen was reached by slowly increasing the dose from 2-5 mg once daily. Bromocriptine holds promise as a safe and orally effective medical treatment to augment surgical or radiotherapeutic measures directed at the pituitary tumour. Its efficacy during longterm administration remains to be established.

Acromegaly↗